Rain can pose a severe threat to a mature and ripening cherry. The ripening cherry acts like a sponge and will quickly absorb water that pools in its stem cup, the natural depression formed in the top of the cherry at the base of its stem. Because the cherry's skin is unable to accommodate the swelling that accompanies the water absorption, an unappealing split occurs in the outer flesh and skin of the fruit. This splitting is not only unsightly, it is also a breeding site for molds and bacteria. A crop of cherries with excessive splitting is of little value to an orchardist.
Cherries ripen in the very early summer. Rains are a typical occurrence for this time of year in cherry growing regions, worldwide. If several rains occur in the period prior to harvest, but while the cherries are susceptible to splitting, the costs incurred by orchardists to adequately helicopter dry their orchard can quickly eat up any anticipated profit.
Currently, there are few options for the removal of rain water from cherries. Several strategies have developed to prevent the rain induced splitting of cherries. The most effective strategies currently employed rely on preventing the rain from first contacting the cherry. A rain diffusing or repelling covering over each cherry tree or portion of an orchard is a sure but very expensive solution. The costs incurred in the purchase, installation and maintenance of covering far outweighs the potential benefits for most orchards.
After a soaking rain, many cherry growers without coverings rely upon conventional helicopters to literally shake the rain off the cherries. The extraordinary downdraft induced by the helicopter's beating rotors quickly disperses the water that ponds in the cherry's stem cup, and so halts the absorption of the ponded water into the cherry.
Several problems exist with the use of helicopters for this purpose. A primary problem is that helicopters are expensive and somewhat dangerous to operate. Additionally, if an orchard is on a hill or has overhead obstructions like power lines, wind breaking trees or light poles, the helicopter's use is especailly limited. Such obstruction can render entire areas of the orchard inaccessible, thereby allowing large portions of the cherry crop to split.
Also, even with vigorous helicopter drying, each cycle of rain and splitting will damage a significant portion of the crop. Helicopters are far form being totally effective. A portion of the cherries will be shielded or missed by the helicopter at each pass. Helicopters are also far from gentle on cherries. The ripening cherries are very susceptible to bruising. The beating helicopter blades can inflict as much damage as they are attempting to prevent. Helicopters are too powerful and vigorous to dry cherries without inflicting significant damage to the fruit in their efforts.
Another problem with helicopters is that in the event of widespread rains, they cannot be everywhere they are needed. Their overall number available for orchard drying are typically quite limited in any particular cherry growing area. Smaller orchards are always further down the waiting list from larger orchards that are able to pay much higher fees for the drying service. By the time the smaller orchard, or even the last serviced area of the larger orchard, is treated by the helicopter, the rain's damage to the cherries is already done.
For smaller orchards, a conventional orchard spray rig is often relied upon for some measure of reducing rain damage. The orchard spray rig typically includes a powerful blower pulled behind a tractor. The blower, as it rides close to ground level, forces air up into the trees. For spraying, a row of atomizers around the blower can deliver pesticides and other farm chemicals.
However, the uilization of the conventional spray rig for drying cherries has problems. The spray rig is typically too gentle and has little effect on dispersing rain water from the stem cups. From below the trees, the spray rig's blowers are unable effectively reach the ponded water in the stem cup at the top of each cherry. Additionally, the spray rig's blowers are designed to broadcast material, delivering a diffuse air flow instead of the concentrated blast of air required to dislodge the ponded water.
U.S. Pat. No. 5,586,725 to Ballu discloses an agricultural chemical blower having linear blowing panels. However, the Ballu '725 device requires compressed air to operate. Such a device fails to deliver the volumes of air required to be utilized for drying a crop.
It is little wonder that many orchardists, especially smaller, family owned operations, give up on rain damage prevention, leaving their profits to the whims nature. A cherry drying device is needed that is gentle on the rain soaked cherry, but effectively removes ponded water from the stem cup.
Other crops, especially those that are grown to a height, lack an efficient and cost effective means to reduce the damage caused by rain and moisture. Weather patterns can change from global climatic factors like "El Nino." Growers need the ability to help their crops through cyclical changes in weather. A device is needed that will allow a farmer or orchardist to dry a crop whenever moisture or rain needs to be removed from the crop.
In addition to rains, freezing temperatures can devastate a crop in a matter of hours. Many devices that rely upon circulating the inversion layer of warmer air down to the level of the crop are known. One such device is the orchard heat exchanger invented by the present inventor, James Siebol. In his issued U.S. Pat. No. 5,305,548, Siebol disclosed a dual propeller fan system. The Siebol '548 apparatus is inherently large, due to the required internal combustion engine enclosed with in the shroud of the device. Additionally, the Siebol '548 device only mentions cherry drying and spray applications in the brief description of the invention in passing. A need exists for an improved dual propeller fan system with the basic configuration of the Siebol '548 device, but more economical to build and having broader applications in the farm or orchard. A related need exists for an agricultural air handler that details a specific apparatus and method for agricultural spraying and crop drying.
Another problem with internal combustion engine located at the top of an extending "lift" is that the vibrations from the engine require a more sturdy construction (and support) than if such an engine were not present. Additionally, the size of an internal combustion engine requires the shroud to be large and bulky. The shroud must also be easily accessible to aid in the frequent maintenance that an internal combustion engine inherently requires. A device is needed that can provide efficient and effective heat exchange at a reasonable expense for the small orchardist or grower.